The documentary mentioned "Say Amen, Somebody" was just released on DVD, available through Amazon.com.
I'll look it up. Thanks.
HOW did I miss this???
“SAY, AMEN, SOMEBODY” is one of the most joyful movies I've ever seen. It is also one of the best musicals and one of the most interesting documentaries. And it's a terrific good time. The movie is about gospel music, and it's filled with gospel music. It's sung by some of the pioneers of modern gospel, who are now in their seventies and eighties, and it's sung by some of the rising younger stars, and it's sung by choirs of kids. It's sung in churches and around the dining room table; with orchestras and a capella; by an old man named Thomas A. Dorsey in front of thousands of people; and by Dorsey standing all by himself in his own backyard. The music in “Say Amen, Somebody”is as exciting and uplifting as any music I've ever heard on film.
http://www.ebertfest.com/four/say_amen_rev.htm